1. Field of the Invention
The present invention relates to a medical bed.
2. Description of the Prior Art
Medical beds or tables comprise a base and a platform supporting the patient. Also included are means for adjusting the height, and the longitudinal and lateral slope of the platform. The platforms of such beds or tables comprise several sections which are adapted to be displaced with respect to one another. Such a surgical table is described in French patent application 1.306 095 filed Aug. 30, 1961 by RITER COMPANY INC.
According to this patent, the height and slope adjustment means of the platform are located in the base. These adjustment means comprise a vertical central jack adapted to adjust the height of the platform, two lateral jacks for adjusting the slope of the platform by rotating the platform around a longitudinal axis, and a jack for rotating the platform around a transverse axis. This embodiment also provides the base of the table with one or several platforms which receive one of the ends of the lateral jacks. These platforms are adapted to be raised and lowered conjointly with the movement of the central jack rod so as to permit the adjustment of the slope of the platform when it is in its highest position. This embodiment also provides the base of the table with vertical guiding slides for the platforms and with an apparatus to transmit the movement of the central jack rod to the platform.
This invention requires the use of numerous mechanical elements, which increases the weight of the table and increases the cost of manufacture of such a table.
In addition, to these features described in this French patent, medical beds or tables are generally furnished with a platform having several sections corresponding respectively, to the dorsal zone, to the femoral zone and to the zone of the lower extremities of the patient.
These different sections are journalled on each other and are adapted to be displaced with respect to each other. Generally the means employed for displacing a section with respect to another section comprises a hydraulic jack fixed at one end to two tabs, respectively, integral with two sections. The main disadvantage of this embodiment is that in order to have a sufficient displacement of one section with respect to another section, the stroke length of the jack rod must be relatively large. In addition, when the rod is completely opened out from the body of the jack, the forces exerted thereon tend to prematurely wear out the guiding bore of this rod. As a result, the jack will lose its waterproof quality. Also, the beds or tables of the prior art are not furnished with means sufficient to permit a lateral tilting of the platform in the two directions and to arrange the platform in a vertical position and along a rearward slope position.